Directory path

[DeaD_EyE]

As anchor you can use different locations or you work with absolute paths, which makes your program less flexible.

If you use the current working directory, you have to be in the right path, if you execute the program. This is not very usable, if the program lives somewhere on your path. When your program is somewhere in /usr/bin or C:\Windows\system32\, the working directory differs from Path, where the executable file is.

For myself I use the executable itself as anchor and define, all directories next to the executable. Here an example:

import sys
from pathlib import Path

cwd = Path.cwd()
exe = Path(sys.argv[0]).resolve().parent

print('Current working directory:', cwd)
print('Directory of executable:', exe)
print('Directory for images next to executable', exe / 'images')

If you have for example this structure:

Output:
|- project_test/
   |- bin/
      |- your_program
   |- docs/
      |- Mastering_Natural_Language_Processing_with_Python.pdf
      |- learning_numpy_array.pdf
   |- images/
      |- siemens_updates.jpg
      |- 11106-256x256x32.png
      |- x_vs_xor_vs_aes.png

The program:

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#!/usr/bin/env python3

"""
This program prints only the content of the directories docs and images.
The images are opened with PIL and their size is printed to console.
The pathlib module has been used to demonstrate how easy it is, 
to do object oriented path manipulation.

This can be very helpful, if your program has no fixed location in your system,
where the location of the program itself defines the location of ressources.
"""


import sys
from pathlib import Path
from PIL import Image

cwd = Path.cwd()
# current working directory could be any location in system path

exe = Path(sys.argv[0]).resolve().parent
# sys.argv[0] holds the scriptname as str, which is executing
# putting this in a Path() makes a Path object from it
# the method resolve removes the dots in the path
# and makes the path absolute.
# The parent attribute holds the parent part of the path
# If the path was before a file, the parent is it's directory
# If the path was a directory, then it's the directory above
# The benefit of pathlib is, that it works with Linux, MacOS and Windows.
# If you're using the API of this module, you're on the safe side.
# The abstraction and some os differences are handled by this module

images = exe.parent / 'images'
docs = exe.parent / 'docs'
# parent means the previous part of the path
# goes one directory up

print('Current working directory:', cwd)
print('Directory of executable:', exe)
print('Images:', images)
print('Docs:', docs)

print()
print('Listing content of docs')
for file in docs.glob('*.pdf'):
    print(file)
print()


print('Listing content of images')
for file in images.glob('*.png'):
    img = Image.open(file)
    width, height = img.size
    print(f'Found image {file} with size {width}x{height}')

If you plan to put your project into a zip file, together with resources, it's different.
But I guess you're not so far. First you should try pathlib, which helps a lot.

Edit: Instead of getting absolute paths of images, you can do it with the executable files. Another solution could be, to put the executable files in the system path, but this makes less fun.